Shotgun gauge adapter



1964 E. T. MELLOR ETAL 3,

SHOTGUN GAUGE ADAPTER Filed Feb. 26, 1963 2 Sheets-Sheet 1 Nov. 17, 1964 Filed Feb. 26, 1963 E. T. MELLOR ETAL SHOTGUN GAUGE ADAPTER 2 Sheets-Sheet 2 INVENTORS E 7241/17 7: Mel/arr dew/1n KunsEv/ch United States Patent 3,156,995 SHQTGUN GA GE ADAPTER Erwin T. Mellon, Qhicopee Falls, and l'ohn E. Konsevieh, \Chieopee, Mass, assigners to Enihart (Iorporation, a corporation of Connecticut Filed Feb. 26, 1963, Ser. No. 261,042 3 Claims. (Cl. 42- 77) This invention relates to shotgun gauge adapters, and more particularly to adapter tubes removably insertable in the barrel of shotguns to enable the same gun to fire diiferent gauge shells.

The principal object of this invention is to provide an improved shortgun gauge adapter capable of use with various types of shotguns. For example, by use of this adapter any standard 12 gauge shotgun can be adapted to fire a .410 gauge by simply inserting a tube in the breech end of the barrel. When it is desired to fire 12 gauge shells, the tube can be readily removed. Moreover, the constructional characteristics of the tube are such that insertion and removal is accomplished without injury to the barrel.

The above and other objects and advantages of this invention will be more readily perceived from the following description with reference to the accompanying drawings in which FIG. 1 is a partial perspective view showing an adapter tube embodying this invention being inserted into a shotgun barrel;

FIG. 2 is an elevational view partly in section showing an adapter tube disposed within the barrel of a gun;

FIG. 3 is a partial elevational view on an enlarged scale showing the breech end portion of the adapter within a gun barrel;

FIGS. 4 and 5 are bottom partial views showing parts of the adapter in different operative relationships; and

FIG. 6 is a perspective View of an element of the adapter.

Referring now in detail to the drawing, a shotgun gauge adapter embodying this invention is shown generally at 6 in FIG. 1. The adapter is in the form of a tube removably insertable into the barrel 8 of any standard shotgun, shown generally at It). The shotgun shown is a break-action type and includes an extractor l2 operated to extract expended shells when the barrel is opened.

In accordance with this invention, the adapter 6 comprises an elongated metallic tube which may be made of steel, aluminum or other suitable material. The adapter tube 6 is provided with a flange 14 disposed at one end. The forward face of the flange is beveled, such as best shown at 16 in FIG. 3. This bevel is designed to mate with the bevel 13 in the breech end of the barrel of any standard shotgun. Thus when the tube is pushed fully into the barrel the beveled flange centers the tube with n the barrel. The flange 14 only extends around the upper portion of the tube leaving a cutaway or slot 15. The slot permits free movement of the extractor 12; the slot extends through a sufficiently large angle to accommodate the largest extractors found on standard model shotguns.

In addition to the flange or header 14, centering means is also provided at the opposite end of the tube and comprises a flexible resilient ring Zti, as shown in FIG. 2. The ring is disposed adjacent the outer end of the tube and is disposed in a slot 21. The ring may be made of any suitably flexible or elastic material such as various synthetic plastics, and including Teflon, neoprene, rubber and the like. The outer diameter of the ring is made sufiiciently large to provide a snug fit in the barrel so that when the adapter is inserted in the barrel the ring will hold it centered and prevent the barrel being scratched by contact with the metal tube. In addition the ring 20 is suificiently tight to form a gas seal which prevents rearward escape of the gases.

Configuration of the adapter tube forward of the flange or header 14 is cylindrical as shown at 22 (FIG. 2). This cylindrical portion has an outer diameter somewhat smaller than the barrel so as to provide clearance. Forward of the section 22, the adapter tube is provided with a slot 23 in which is fitted a clamp or ring 24; this serves to hold an extractor member 26 in place in slot 28 in the underside of the tube. Immediately forward of the slot 22, the tube continues in cylindrical cross section for a sufficient distance to provide the chamber for a shotgun shell, shown at 3% in FIGS. 2 and 3.

From the chamber portion the tube tapers inwardly, as shown at 31 in FIG. 2, whereby a substantial reduction in the overall weight of the adapter is achieved. At its outer end, the tube diameter increases again to provide suflicient thickness of metal for the ring-retaining slot 21. The inner bore of the tube at the terminal end thereof is tapered outwardly, as shown at 34 in FIG. 2. This tapered surface prevents objectionable build-up of burned powder residue on the outer end of the tube.

The extractor member 26, preferably a spring metal bar, is held in place in slot 28 by means of the spring steel clamp 24 fitted in the recesses 23. The clamp 24 is reversible to vary the stroke of extractor 26 as will be explained below. The clamp 24 (FIG. 6) is generally semi-cyclindrical in configuration with a flattened portion 36 disposed diametrically opposite opening 37 enabling the clamp to be removed and installed in the slot 23.

A spring finger 33 extends axially from the flattened section 36 of the ring and is deflected inwardly of the plane of section 36. With the clamp disposed in the slot 23 the spring finger engages the floor of slot 42 provided in the extractor bar 26. The spring finger 38 thus urges the extractor upwardly into surface-to-surface contact with the slot 28 in the underside of the tube 6 insuring correct disposition of the upwardly extending lug 46 (FIG. 3) for engagement with a shotgun shell flange. A downwardly extending lug 48 is provided opposite the lugs 46; this is of similar configuration to engage and be operated by the extractor 12 of the shotgun.

When the shotgun barrel is opened and extractor l2 moved rearwardly, the extractor bar 26 is carried rear- Wardly until the edge 43 of the slot comes into contact with the clamp 24. When the action is closed, the breech face 59 (FIG. 1) of the shotgun handle engages in succession the extractor 12, the extractor bar 26 and the shotgun shell moving them forwardly.

As shown in FIGS. 3 and 4 the clamp 24 may be positioned with finger 38 disposed toward the breech end of the adapter tube for shotguns having a long extraction stroke. As shown in FIG. 5 the clamp may be reversed simply by snapping it off the tube and refitting it thereon with the finger 38 extending toward the muzzle end of the adapter. In this position of the clamp 24, the adapter may be used with shotguns having a short extraction stroke. In the latter position, the terminal end of the finger 3% acts as a stop when contacted by wall 43 of extractor slot 42. The reversible clamp assures that the extractor stroke of the bar as will be the same length as the long or short extractor strokes of standard types of shotguns. To achieve this purpose, the length a (FIG. 6) of the finger 38 is made equal to the difference in length between the long and short extraction strokes of standard shotguns.

To use the adapter embodying this invention it is preferable to lightly oil the resilient ring 20 at the muzzle end of the adapter. Then with the extractor clamp 24 disposed in accordance with the length of the extractor stroke of the particular gun, the adapter is simply pushed into the breech end of the shotgun barrel 8 as though a it were a shotgun shell. In doing this the smaller extractor 26 on the adapter tube is lined up so that it will be centered on the larger extractor 12 of the gun. The adapter is pushed all the way into the barrel so that it is flush with the breech end thereof. The gun can now be loaded and operated using the smaller gauge shells in exactly the same manner as in using larger gauge ammunition.

Having thus described this invention, what is claimed 1. Shotgun gauge adapter to enable one gun to tire shells of different gauge, said adapter comprising a tube having an inner bore corresponding in diameter to the smaller gauge shells to be flared, said tube being provided with a flange at its breach endhaving a bevel corresponding to the bevel of the breech end of said shotgun and adjacent its muzzle end a flexible ring projecting from the outer surface of the tube and of sutficient diameter to fit snugly within the barrel of said shotgun, said flange and ring serving to center the tube in said barrel, the outer surface of the tube having a diameter less thansaid barrel to provide a clearance, said ring also serving as a seal to prevent the rearward escape of gases, an extractor disposed to be operated by the extractor of said shotgun, and a clamp holding the extractor of the adapter tube in place on said tube, said clamp being reversibly positionable on said tube to change the length of the stroke of the extractor carried by said tube.

2. A shotgun gauge adapter as set forth in claim 1 adjacent the breech end of said tube into which said ring is fitted, said ring including an axially extending finger deflected inwardly of the plane of the ring and engaged with the axially slidable extractor to urge the I latter into its operative position, said finger also providing a stop for said slidable extractor, when disposed toward the muzzle end of said tube for short slidable extractor stroke shotguns and when disposed toward the breech end of said tube permitting said extractor to be moved for along extractor stroke.

3. Shotgun gauge adapter to enable one barrel to fire shells of different gauge, said adapter comprising a tube removably insertable in said barrel, said tube having an extractor axially slidable in a slot disposed adjacent its breech end, a spring steel clamp fitted around said tube retaining said extractor in operative position, said clamp including an axially extending finger which when disposed towards the muzzle end of said tube is engageable with said extractor to limit its extracting stroke, said clamp being reversible on the tube to enable positioning said finger toward the breech end of said tube whereby the stroke of said extractor is changeable to conform with extractor strokes of dififerent types of shotguns.

No references cited. 

1. SHOTGUN GAUGE ADAPTER TO ENABLE ONE GUN TO FIRE SHELLS OF DIFFERENT GAUGE, SAID ADAPTER COMPRISING A TUBE HAVING AN INNER BORE CORRESPONDING IN DIAMETER TO THE SMALLER GAUGE SHELLS TO BE FLARED, SAID TUBE BEING PROVIDED WITH A FLANGE AT ITS BREACH END HAVING A BEVEL CORRESPONDING TO THE BEVEL OF THE BREECH END OF SAID SHOTGUN AND ADJACENT ITS MUZZLE END A FLEXIBLE RING PROJECTING FROM THE OUTER SURFACE OF THE TUBE AND OF SUFFICIENT DIAMETER TO FIT SNUGLY WITHIN THE BARREL OF SAID SHOTGUN, SAID FLANGE AND RING SERVING TO CENTER THE TUBE IN SAID BARREL, THE OUTER SURFACE OF THE TUBE HAVING A DIAMETER LESS THAN SAID BARREL TO PROVIDE A CLEARANCE, SAID RING ALSO SERVING AS A SEAL TO PREVENT THE REARWARD ESCAPE OF GASES, AN EXTRACTOR DISPOSED TO BE OPERATED BY THE EXTRACTOR OF SAID SHOTGUN, AND A CLAMP HOLDING THE EXTRACTOR OF THE ADAPTER TUBE IN PLACE ON SAID TUBE, SAID CLAMP BEING REVERSIBLY POSITIONABLE ON SAID TUBE TO CHANGE THE LENGTH OF THE STROKE OF THE EXTRACTOR CARRIED BY SAID TUBE. 